• Asian-Australasian Journal of Animal Sciences
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• 제21권9호
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• pp.1324-1329
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• 2008

This study was conducted to evaluate the potential of the transformed Lactobacillus reuteri Pg4 (T-Pg4) harboring the ${\beta}$-glucanase gene as a poultry probiotic. The probiotic properties of the T-Pg4 strain were evaluated in vitro by their adherence capability and acid and bile salt tolerance, and were evaluated in vivo by their survival and adhesion in the gastrointestinal tract (GIT) of specific-pathogen-free (SPF) chickens. The results showed that the T-Pg4 strain exhibited resistance to acidic conditions and contact with bile salt, and adhered efficiently to the crop and intestinal epithelial cells of chickens in vitro. The T-Pg4 strain also could survive and colonize the gastrointestinal epithelium of the experimental SPF chickens in vivo. In addition, radial enzyme diffusion was used to demonstrate that the Lactobacillus spp. randomly isolated from the GIT of the SPF chickens fed T-Pg4 possessed ${\beta}$-glucanase secretion capability. These findings have demonstrated that the transformed L. reuteri Pg4 survives transit through the stomach and intestine, and may secrete ${\beta}$-glucanase in the chicken GIT. Therefore, it is suggested that this organism could be used as a multifunctional poultry probiotic.

• Ocean and Polar Research
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• 제27권2호
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• pp.221-230
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• 2005

Recently there has been a rapid accumulation of knowledge of microbial life in cold and frozen ecosystems. This understanding has revealed the extensive diversity of psychrophilic prokaryotes. Cultivation-based and molecular-based surveys have been performed in Antarctic habitats ranging from glacial ice to continental shelf sediments. Results indicate that psychrophilic taxa permeate throughout the Bacteria while they represent a more mysterious element of diversity in the Archaea owing to a notable lack of cultured strains. In certain cold climate ecosystems the diversity of psychrophilic populations reach levels comparable to the richest temperate equivalents. Within these communities must exist tremendous genetic diversify that is potentially of fundamental and of practical value. So far this genetic pool has been hardly explored. Only recently have genomic data become available for various psychrophilic prokaryotes and more is required. This owes to the fact that psychrophilic microbes possess manifold mechanisms for cold adaptations, which not only Provide enhanced survival and Persistence but Probably also contributes to niche specialisation. These mechanisms, including cold-active and ice-active proteins, polyunsaturated lipids and exopolysaccharides also have a great interest to biotechnologists.

• 한국식품영양학회지
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• 제31권3호
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• pp.319-327
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• 2018

This paper defines the common features of synbiotics based on the definition of probiotics and prebiotics, and reviews the effectiveness of synbiotic food. The concept of synbiotics is defined as 'a mixture of prebiotics and probiotics that have a beneficial effect on the host, as a dietary supplement that alters living organisms in the gastrointestinal tract and improves their survival.' Synbiotic food contains ingredients with beneficial microbes that are expected to improve interactions between microbial and useful substances. Synbiotic foods may have anti-cancer and immune system-boosting effects. Improved digestion, healthier bowel movements, and overall increased intestinal health has been reported were reported after increasing the healthy microorganisms within the intestinal tract. In addition, depending on the type of food containing the symbiotic ingredients, more consistent weight control, improvement of cardiovascular health, and lower blood glucose levels may also be expected. Unlike previous studies, this review of synbiotics has shown that it is necessary for synergistic effects to take place among microorganisms and components to be further studied. Further research is needed on the safety and ingestion of microorganisms contained in synbiotics.

• The Journal of Advanced Prosthodontics
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• 제4권3호
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• pp.134-138
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• 2012

PURPOSE. The study was conducted to evaluate the efficacy of implant supported tooth replacement in diabetic patients. MATERIALS AND METHODS. The study involved placement of implants (UNITI implants, Equinox Medical Technologies, Zeist, Holland, diameter of 3.7 mm and length 13 mm) in five diabetic patients (three females and two males) of age ranging from 35-65 years with acceptable metabolic control of plasma glucose. All patients included in the study were indicated for single tooth maxillary central incisor replacement, with the adjacent teeth intact. The survival of the restored implants was assessed for a period of three months by measurement of crestal bone heights, bleeding on probing and micro flora predominance. Paired t-test was done to find out the difference in the microbial colonization, bleeding on probing and crestal bone loss. P values of less than 0.05 were taken to indicate statistical significance. RESULTS. Results indicated that there was a significant reduction in bleeding on probing and colonization at the end of three months and the bone loss was not statistically significant. CONCLUSION. The study explores the hypothesis that patients with diabetes are appropriate candidates for implants and justifies the continued evaluation of the impact of diabetes on implant success and complications.

• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.196-199
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• 2003

We investigated the antagonistic effects of two lactococcal bacteriocins, nisin or lacticin NK24, on the growth and the survival of Listeria monocytogenes in vacuum or modified atmosphere-packaged ground beef, Ground beef was inoculated with approximately 3 log colony-forming units (CFU) of L. monocytogenes ATCC 15313 culture per gram of ground beef. Inoculated samples were blended with/without 100 AU/g nisin or lacticin NK24, and subsequently vacuum or modified atmosphere packed at 4$^{\circ}C$. Listeria in the bacteriocin-treated and control samples was subsequently isolated from both vacuum and modified atmosphere packs and enumerated as CFU on Listeria Isolation Agar medium. Microbial counts in ground beef treated with bacteriocin declined steadily, while those of non-treated beef samples increased steadily. The results obtained demonstrate that nisin inhibits the growth of L. monocytogenes more effectively than lacticin NK24 at 100 AU/g. The use of lactococcal bacteriocins, such as nisin or lacticin NK24, in vacuum or modified atmosphere packaging offers a promising approach for eliminating or reducing the risk of L monocytogenes contamination in ground beef.

• 미생물학회지
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• 제9권2호
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• pp.47-54
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• 1971

This study is concerned to the microbial population and its effects in the fish paste products. Experimental results were summarized as following orders ; 1) The number of bacteria in accordance with raw materials and coocking site waas known to as ; Wheat flor - $7.0{\times}10^8$/gram , Brayed fish meat - $2.0{\times}10^7$/gram, Cooking table - $6.1{\times}10^6$/$1.54cm^2$Chopped fish meat -$4.1{\times}10^6$/gram, Wooden plate - $5.5{\times}10^5$/218.32cm, Sodium chloride - $8.8{\times}10^4$/gram, Wheat starch - $4.5{\times}10^4$/gram, Fish meat - $2.3{\times}10^4$/gram. However, there were a few bacterial numbers less than 300 per gram of raw materials, such as monosodium glutamate, tap water, sugar, saccharine and eggs. 2) Bacterial population in the raw materials might be changed according to the conditions of preservation. 3) When the heat tratment is used for the preservation, the thermal effects were rarely found at the interior part of fish paste products. Conduction of heat into the interior part dose not rise about $84^{\circ}C$ and the survival of bacteria could be possible under the condition. Therefore, cooking being used requires further studies. 4) Number of bacteria in the fish paste products sold in the market was higher on April and May than those on June. Especially on June, the number of bacteriz in the interior part were found higher than those in the exterior part of the products.

• Geomechanics and Engineering
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• 제17권5호
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• pp.475-483
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• 2019

Vegetation cover plays a vital role in stabilizing the soil structure, thereby contributing to surface erosion control. Surface vegetation acts as a shelterbelt that controls the flow velocity and reduces the kinetic energy of the water near the soil surface, whereas vegetation roots reinforce the soil via the formation of root-particle interactions that reduce particle detachment. In this study, two vegetation-testing trials were conducted. The first trial was held on cool-season turfgrasses seeded in a biopolymer-treated site soil in an open greenhouse. At the end of the test, the most suitable grass type was suggested for the second vegetation test, which was conducted in an environmental control chamber. In the second test, biopolymers, namely, starch and xanthan gum hydrogels (pure starch, pure xanthan gum, and xanthan gum-starch mixtures), were tested as soil conditioners for improving the water-holding capacity and vegetation growth in sandy soils. The results support the possibility that biopolymer treatments may enhance the survival rate of vegetation under severe drought environments, which could be applicable for soil stabilization in arid and semiarid regions.

• 미생물학회지
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• 제53권1호
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• pp.20-28
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• 2017

감마선, 전자빔 등과 같은 전리방사선과 자외선을 이용하는 물리적 멸균방법은 살균 효과와 경제성이 우수하므로 다양한 산업분야에서 사용되고 있으나, 미생물의 돌연변이를 유발하는 요인으로 작용할 수 있다. 본 연구에서는 전리방사선 및 자외선의 유전학적 안전성을 평가하기 위해서 Salmonella enterica와 Escherichia coli 균주에 자외선, 감마선, 전자빔을 조사한 후에 생존율, 돌연변이율, DNA 손상 효과를 조사하였다. 자외선, 감마선, 전자빔의 조사선량이 증가함에 따라 시험 균주의 생존율이 모두 급격히 감소하였으며, 90% 이상이 사멸되는 조사선량은 각각 $0.40{\sim}25.06mJ/cm^3$, 0.11~0.22 kGy, 0.14~0.53 kGy 이었다. SOS/umu-test에서는 자외선, 감마선, 전자빔에 노출된 모든 시료에서 DNA 손상을 유발하는 유전독성이 확인되었다. Ames test에서는 자외선과 감마선에 노출된 후에 복귀 돌연변이율이 각각 $3.82{\times}10^{-4}$, $9.84{\times}10^{-6}$까지 증가하였다. S. enterica TA100의 사멸율이 99.99% 이상 되는 선량의 자외선, 감마선, 전자빔에서의 복귀 돌연변이율은 각각 자연돌연변이율 대비 347배, 220배, 0.6배 증가하였다. E. coli CSH100 균주를 자외선, 감마선, 전자빔에 노출시킨뒤에 조사한 리팜피신내성 돌연변이율은 각각 $2.46{\times}10^{-6}$, $1.66{\times}10^{-6}$, $4.12{\times}10^{-7}$ 이었다. 따라서 사멸효과의 관점에서는 감마선 처리가 미생물 제어에 효과적이라 할 수 있으며, 전자빔은 DNA 손상과 세균돌연변이를 적게 유발하며 사멸효과를 얻는 장점이 있다고 생각된다.

• 한국토양비료학회지
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• 제25권4호
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• pp.370-377
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• 1992

작물재배기간중(作物栽培期間中) 재배작물(栽培作物)의 종류(種類), 잔사(殘渣)의 토양환원(土壤還元) 및 시비량(施肥량)을 달리 했을때 토양미생물(土壤微生物)의 종류(種類)와 수(數), 토양이화학성(土壤理化學性), 작물생육등(作物生育等)에 미치는 영향(影響)을 알고자 일연(一連)의 포장시험(圃場試驗) 및 실내시험결과(室內試驗結果)를 요약(要約)하면 다음과 같다. 1. 작물(作物)의 종류별(種類別) 미생물수(微生物數) 변화(變化)는 밭벼 재배토양(栽培土壤)에서 세균(細菌)과 방선균(放線菌) 수(數)가 많았으나 고추와 참깨재배토양(裁培土壤)에서 세균(細菌), 방선균(放線菌) 및 사상균수(絲狀菌數) 변화(變化)에는 크게 영향(影響)하지 않았다. 2. 생산된 작물잔사(作物殘渣)를 전양환원(全量還元)시 고추, 참깨, 대두(大豆) 및 밭벼토양(土壤) 모두 미생물수(微生物數) 증가(增加)를 보였으며 그 정도(程度)는 밭벼 재배시(栽培時) 세균(細菌)과 방선균(放線菌) 수(數)의 증가(增加)가 더욱 뚜렷하였다. 3. 시비량(施肥量)의 증가(增加)는 공시(供試)된 4개(個) 작물(作物)에서 모두 미생물수(微生物水)의 현저(顯著)한 감소(減少)를 보였으며 특(特)히 방선균(放線菌)의 감소(減少)가 더욱 현저(顯著)하였으며 수확후(收穫後) 미분해(未分解) 작물(作物) 잔사환원(殘渣還元)은 시비량증가(施肥量增加)로 인(因)한 미생물수(微生物數) 감소(減少)를 막아주는 완형작용(緩衡作用)의 기능(機能)을 보였다. 4. 공시토양(供試土壤)의 세균(細菌) 분리동정결과(分離同定結果) 바실러스속(屬)>리조비움속(屬)>아그로박테리움속(屬)>슈도모나스속(屬) 세균(細菌)의 순(順)으로 균수(菌數)가 많았으며 전체적(全體的)으로 볼때 그램양성균(陽性菌)이 그램음성균수(陰性菌數)보다 많았다. 5. 작물별(作物別) 세균(細菌)의 종난(種難)와 수(數)를 보면 바실러스속(屬) 세균(細菌)은 고추에서, 리조비움속(屬)은 대두(大豆)와 참깨에서, 아그로박테리움속(屬)은 대두(大豆) 및 참깨재배지(栽培地)에서 많은 수(數)를 보였다. 6. 미생물(微生物)의 서식지별(棲息地別) 수(數)는 근표면(根表面)이 토양(土壤)이나 근권(根圈)에 비해 수십배(數十培) 내지(乃至) 수백배(數百培) 이상(以上) 많았으며 다음은 근권(根圈)이었다. 바실러스속(屬), 리조비움속(屬) 및 슈도모나스속등(屬等)의 세균(細菌)은 근표면(根表面)에서 뚜렷이 많은 수(數)를 보였고 아그로박테리움속(屬) 세균(細菌)과 후사리움속(屬) 사상균(絲狀菌)은 근권(根圈)에서 많았다. 7. 작물재배지(作物栽培地) 토양(土壤)에서 미생물수변화(微生物數變化)에 미치는 영향(影響)은 기후(氣候)>작물(作物)>유기물(有機物)>시비양(施肥量)의 순(順)으로 컸다.

• 농업과학연구
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• 제44권4호
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• pp.558-565
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• 2017

This study was conducted to determine the effect of inoculation of microorganism isolated from pig feces on nutrient contents of fermented hulless barley. The microbial flora in feces of a total of four crossbred piglets ($Landrace{\times}Yorkshire{\times}Duroc$) was analyzed by 16s rRNA sequencing. The most abundant strain was then selected for fermentation of hulless barley. Lactobacillus plantarum (L. plantarum) was dominant (64.56%) in intestinal microbial flora in the pig feces. The selected candidate strain showed significantly higher survival rate at pH 7 than at pH 2.5 and 3.0 (p < 0.05). Incubated culture containing the candidate strain showed an increased growth rate with lower pH levels after 7.5 h incubation compared to initial incubation period (p < 0.05). When compared with commercial multiple probiotics which were used as control, the selected strain showed faster growth rate at 5 h post-incubation (p < 0.05). During the fermentation period, neither inoculated nor non-inoculated control hulless barley showed any change in pH value. Crude fat, fiber and ash contents were lower (p < 0.05) in hulless barley inoculated by the selected strain compared to control. However, moisture, energy, NDF and ADF were not affected by the inoculation of strain or fermentation period. Lactic acid was increased and acetic acid was decreased in the hulless barley inoculated with the selected strain during the fermentation period (p < 0.05). Taken together, our results suggest that L. plantarum derived from the pigs could be utilized as a new microorganism for manufacturing fermented feed stuffs.